Moulding

ABSTRACT

The invention provides methods for molding three-dimensional products from a mass of foodstuff which is suitable for human consumption, in particular from a mass of meat. 
     The method comprises feeding the mass of foodstuff into a mold cavity, molding the mass of foodstuff into a molded product, and removing the molded product from the mold cavity using pressurized gas.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a division application of U.S. patent application Ser. No.11/758,567 filed Jun. 5, 2007, which issued as U.S. Pat. No. 7,597,549on Oct. 6, 2009, which is a continuation application of U.S. patentapplication Ser. No. 10/806,714, filed Mar. 23, 2004, which issued asU.S. Pat. No. 7,284,973 on Oct. 23, 2007, and which is a divisionalapplication of U.S. Ser. No. 09/863,933, filed May 23, 2001, whichissued as U.S. Pat. No. 6,811,802 on Nov. 2, 2004 and which is acontinuation in part application of International Application No.PCT/NL99/00701 filed Nov. 16, 1999, which claims priority to DutchApplication No. 1010630 filed Nov. 23, 1998, the contents of all ofwhich are incorporated by reference herein.

FIELD OF THE INVENTION

The present invention relates to the field of moulding three-dimensionalproducts from a mass of foodstuff which is suitable for humanconsumption. In particular, the invention relates to the production ofmoulded portions of a foodstuff starting from a mass of the foodstuff inquestion, which mass is of substantially pasty, pulpy consistency. Theinvention relates in particular to the moulding of edible products froma mass which predominantly comprises pounded meat, in particular chickenor other poultry meat, but also beef, pork, etc. The invention alsorelates to the moulding of products from fish, dough, etc.

BACKGROUND OF THE INVENTION

With regard to the processing of poultry meat, the invention is based onthe recognition that the processing of poultry produces low-qualitymeat, for example meat which has been mechanically removed from the boneand meat trimmings, which can be given a higher added value by beingupgraded. Also, there is an increasing consumer demand for “moulded meatproducts”, for example for snacks, and for meat products with anattractive appearance. In these sectors, demand may change quickly, sothat it must be possible to adapt the production method according to theinvention quickly to meet demand. Furthermore, it is observed that thedemand for moulded (meat) products is very high, and consequently itmust be possible to achieve a high production capacity.

Various methods and moulding machines are known for moulding productsfrom a (meat) mass, and a number of these methods and moulding machineswill be described briefly below.

U.S. Pat. No. 4,987,643 has described a moulding machine of the“slide-plate” type, for the purpose of producing portions of hamburgermeat. A machine of this nature has a substantially planar moulding platecontaining a plurality of mould cavities for the meat mass. The mouldingplate can be moved to and fro substantially in its horizontal plane forthe purpose of displacing the mould cavities between a filling position,in which the mould cavities are filled with meat mass which has beenplaced under pressure by a meat pump, and a removal position, in whichthe moulded meat products are removed from the mould cavity. Thecapacity of a slide-plate machine of this nature is limited inparticular by the rate at which the mould plate can be moved to and fro;it is necessary for the mould plate of the known machine to come to astandstill at the filling and removal positions. The speed of movementof the mould plate is limited by the inertia forces which are generatedby the heavy mould plate which is moving to and fro and the componentswhich are connected thereto. The reciprocating movement is partlylimited by the fact that the mass which is introduced into the mouldcavity under a filling pressure has to remain in the closed mould cavityfor a certain period in order to obtain the desired cohesion or adhesionof the pieces of meat. The design of these known moulding machines ofthe slide-plate type has proven unsuitable or, at any rate,disadvantageous for further increasing the production capacity, whichwould be desirable in view of the increasing demand for moulded meatproducts.

Another known type of moulding machine for meat products and the like isthe “turret-type”, an example of which is described in U.S. Pat. No.4,193,167. In this type of moulding machine, the mould cavities arearranged on a horizontal rotating wheel which can be rotated about avertical axle. The mould cavities have an opening on the underside ofthe rotary wheel, so that the mould cavities extend parallel to the axisof rotation of the rotary wheel. Opposite the opening of the mouldcavity, this known moulding machine has a mechanically displaceablebase, the movement of the base being derived, via a cam-disc mechanism,from the rotation of the rotary wheel. The operation of the associatedfilling device is synchronized with respect to the rotation of therotary wheel. In this known moulding machine, the large number of andinteraction between the moving components again limits the extent towhich the capacity can be increased. Particularly when removing themoulded products, the adhesion of the meat mass to the side wall and thebase of the mould cavity represents a problem for operating with successat high speed. The way in which the mould cavities are filled in thisknown machine also limits the production capacity.

Another type of moulding machine for moulding three-dimensional productsfrom a meat mass or the like is the “rotating drum type”. Known mouldingmachines of this type have a rotatable drum which is driven incontinuous rotation by an associated drive, with a plurality of mouldcavities on the outside of the drum, which cavities, in a fillingposition, move past a filling component which is arranged along theoutside of the drum and by means of which the mould cavities are filledwith (meat) mass. In a removal position, which is located further on inthe direction of rotation of the drum, the moulded meat products aredriven out of the mould cavities. In this type of machine, the mouldcavities are located transversely with respect to the axis of rotationof the drum.

Examples of known moulding machines of the “rotating drum type” aredescribed in U.S. Pat. No. 3,504,639, U.S. Pat. No. 3,851,355, U.S. Pat.No. 4,212,609, GB 2,259,043, FR 2,491,734 and FR 2,538223. Thedevelopment of the moulding machine of this “rotating drum type” iscurrently not sufficiently advanced for achieving the productioncapacity required both currently and in the future, and consequently theabovementioned slide-plate moulding machines have the highest capacityand are used for mass production.

In the following text, it is assumed that a filling pressure is exertedon the (meat) mass which is to be introduced into the mould cavity inorder to fill the mould cavity with a portion of the mass. Therefore,the filling pressure is the pressure which is exerted on the (meat) masswhile the mould cavity is being filled.

In order to ensure that the (meat) pieces of which the mass consistsadhere to one another, thus producing a dimensionally stable product,after the mould cavity has been filled with the (meat) mass, the masshas to be subjected to a fixing pressure for a fixing period which takesplace at some point between the time at which the mould cavity is filledand the time at which the moulded product is removed and during whichperiod the portion of the mass is enclosed in the mould cavity. Afterthe fixing period, an edible product which forms a cohesive unit in athree-dimensional shape is obtained, which product can then be removedfrom the mould cavity.

In known moulding machines, such as for example the moulding machinewhich is described in EP 0,447,003, a portion of the mass is pressedinto the open mould cavity by the filling component under a fillingpressure. Then, the mould cavity is closed by the fact that the mouldingplate with its mould-cavity opening slides away from under the openingof the filling component and moves under a closed top plate. Inevitableleakage from the mould cavity and/or relaxation of the mass in the mouldcavity indicates that the pressure of the mass in the mould cavity fallsslightly after the cavity has been closed. In the context of the presentapplication, the pressure which then prevails in the closed mould cavityis regarded as being the fixing pressure. This fixing pressure remainspresent during the displacement of the mould plate until the mouldcavity reaches the opening in the bottom plate, with the result that themould cavity is opened to atmosphere. In this known moulding machine,the fixing pressure is therefore directly and exclusively related to thefilling pressure, and it is impossible to control the fixing pressureindependently of the filling pressure. Also, the duration of the fillingperiod and the fixing period cannot be influenced independently of oneanother, since they are both determined by the displacement speed of themoulding plate of the moulding machine. A final drawback is that as soonas the opening in the bottom plate is reached, the mass in the mouldcavity, which is still under pressure, immediately seeks to escape fromthe opening which is increasing in size, and this has an adverse effecton the shape of the product.

OBJECT OF THE INVENTION

One object of the invention is to provide measures which lead to atreatment of the mass when producing the edible products which istechnologically optimum with regard to the (meat) mass which is to beprocessed.

A particular object of the invention is to provide measures which makeit possible to control the fixing pressure largely, or preferablycompletely, independently of the filling pressure. As has been stated,the fixing pressure is one of the principal parameters of the mouldingprocess. By providing devices which allow the fixing pressure to becontrolled in this way, it is possible to optimally adapt the operationof each of the said devices to the (meat) mass which is to be processedby the device in question. Thus, there will be an optimum formula foreach mass which is to be processed in order to mould products therefrom,and the perimeters of the formula will in principle comprise the time,the pressure and generally also the temperature. In known mouldingmethods, additives are often added to the edible mass which is to beprocessed in order in this way to allow the moulding process to proceedas desired, but this increases the cost price, and furthermore suchadditions are often deprecated by the consumer. For example, if anexcessively high (filling and/or fixing) pressure is used or if apressure is maintained on a (meat) mass for an excessively long period,there is a risk of fat and/or moisture being pressed out and/or of thecomponents which form the mass becoming segregated. Furthermore, highpressures on the edible mass lead to design problems in the devices,such as at the seal which is required for the filling component.

It should be noted that the operation of filling the mould cavities, inparticular the time involved in filling the mould cavities, is largelydependent on the filling pressure exerted on the mass. Independence ofthe filling pressure and fixing pressure allows the filling and mouldingprocess to be set up optimally, partly with a view to achieving a highcapacity of the device.

Furthermore, the methods and devices according to the invention make itpossible to process numerous different masses, with the emphasis fallingon the processing of meat masses.

A further object of the invention is to minimize the filling pressure.For example, in the method provided according to the invention, thefilling pressure in the case of pounded meat is between 0.2 and 5 bar,and the fixing pressure is between 1 and 15 bar.

A further object of the invention is to provide measures which make itpossible to reduce the mechanical load on the (meat) mass when a mouldcavity is being filled compared to that which is employed in knownmoulding machines. This mechanical load is caused in particular by thefilling pressure and by shear forces which are exerted on the meat mass,for example, when a stripper moves past the opening of the filled mouldcavity. Excessive load on the meat mass damages the structure of themeat and therefore reduces the quality of the product. Furthermore, theshear forces exerted when a stripper of the like moves past may cause anundesirable change in the texture of the product.

A further object of the invention is to propose measures which make itpossible to produce three-dimensionally moulded foodstuffs for humanconsumption with a high capacity. A particular object of the inventionis to allow the moulding of the products to take place as far aspossible in a continuous process, in which the mould cavities move alongtheir path at a substantially constant speed and the filling andemptying of the mould cavities take place as far as possible on acontinuous basis. A particular object of the invention is for themoulded products to be removed from the mould cavities without usingmechanical ejectors, or with only minimal use of such ejectors.

Another object of the invention is to provide solutions for controllingthe influence of the viscosity and other relevant properties of the(meat) mass which is to be fed to the mould cavities on the moulding ofthe product in the mould cavity. In particular, the invention providesfor the preparation of the (meat) mass supplied in a continuous process,during which the (meat) mass can, for example, be cooled or heated andadditives, such as water, spices, colorants and flavourings, egg whites,can be added.

Another object of the invention is to propose measures which make itpossible to arrange differently shaped mould cavities on a mouldingmachine in a simple manner and in a short time, preferably withouthaving to adapt the filling and/or removal system of the mouldingmachine. The invention also aims to make it possible to produce productsof different shapes at the same time using a single moulding machine.

A further object of the invention is to propose measures which ensure ahigh level of hygiene during moulding of the products.

Another object of the invention is to propose measures for producingfoodstuffs with a product body which is composed of a plurality ofparts. This description encompasses, inter alia, layered products,products with an internal filling, etc.

A further object of the invention is to provide measures which allow theoutside of the products to be treated, for example by the arrangement ofa ribbed or grid pattern.

The invention also aims to provide a compact device.

A further object of the invention is to provide measures which allow themoulded products to be packaged efficiently.

SUMMARY OF THE INVENTION

The invention provides an improved method for moulding three-dimensionalproducts from a mass of foodstuff which is suitable for humanconsumption, comprising the steps of:

filling a mould cavity with a portion of the mass via a filling openingwhich is associated with the mould cavity, under the influence of afilling pressure which is exerted on the mass and for a filling period,

closing the filling opening of the mould cavity,

holding the mass in the closed mould cavity for a fixing period,

opening the mould cavity and removing the moulded product.

The improvement comprises the use of fixing-pressure-exerting means,which are designed to exert a fixing pressure which acts on the mass inthe mould cavity after the filled mould cavity has been closed.

The invention furthermore provides devices for carrying out the methodand other devices for moulding three dimensional products from a mass offoodstuff.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a diagrammatic cross section through a first exemplaryembodiment of a moulding device according to the invention,

FIG. 2 shows a diagrammatic cross section through a second exemplaryembodiment of a moulding device according to the invention,

FIG. 3 shows a diagrammatic perspective view of a third exemplaryembodiment of a moulding device according to the invention,

FIG. 4 shows a diagrammatic cross section through a fourth exemplaryembodiment of a moulding device according to the invention,

FIG. 5 shows a diagrammatic cross section through a fifth exemplaryembodiment of a moulding device according to the invention,

FIG. 6 shows a diagrammatic cross section through a sixth exemplaryembodiment of a moulding device according to the invention,

FIG. 7 shows a diagrammatic cross section through a seventh exemplaryembodiment of a moulding device according to the invention,

FIG. 8 shows a diagrammatic cross section through an eighth exemplaryembodiment of a moulding device according to the invention,

FIGS. 8 a-g show examples illustrating the filling pressure and thefixing pressure in possible embodiments of the method according to theinvention,

FIG. 9 shows a diagrammatic cross section through a ninth exemplaryembodiment of a moulding device according to the invention,

FIG. 10 shows a diagrammatic cross section through a tenth exemplaryembodiment of a moulding device according to the invention,

FIG. 11 shows a diagrammatic cross section through an exemplaryembodiment of a mould according to the invention,

FIGS. 12 a, 12 b and 12 c show diagrammatic cross sections throughfurther exemplary embodiment of moulds according to the invention,

FIG. 13 shows a diagrammatic perspective view of a moulding device ofthe rotating drum type, possibly in accordance with one of FIGS. 4-10,in combination with an exemplary embodiment of the feed means for themass,

FIG. 14 shows a variant on the design shown in FIG. 13.

FIG. 15 a shows a diagrammatic, vertical section through an eleventhexemplary embodiment of a moulding device according to the invention,

FIG. 15 b shows a diagrammatic cross section through a twelfth exemplaryembodiment of a moulding device according to the invention,

FIGS. 16 a and 16 b show diagrammatic cross sections through athirteenth exemplary embodiment of a moulding device according to theinvention,

FIGS. 17 a-h show diagrammatic cross sections, in various positions,through the moulding device shown in FIGS. 16 a and 16 b, and

FIGS. 18 a and 18 b show diagrammatic perspective views of a fourteenthexemplary embodiment of a moulding device according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a first exemplary embodiment of a moulding device 100according to the invention for producing edible products ofthree-dimensional shape from an inherently shapeless mass of foodstuffwhich is suitable for human consumption, in particular a mass of pounded(chicken) meat. The moulding device 100 is of the “rotating drum” typeand comprises a rotatable drum 102 which, in an immobile frame (notshown), is mounted in such a manner that it can rotate about an axis ofrotation 103, which in this example is substantially horizontal. Thedrum 102 is driven at a substantially constant rotational speed in adirection of rotation indicated by arrow A by drive means (not shown).

The drum 102 is provided with a plurality of mould cavities 104 whichare distributed over the outer circumference and form openings which runall the way through the drum wall 102 and are thus open on both theouter circumference and the inner circumference of the drum 102.

In order to feed meat mass to the mould cavities 104, an immobilemass-feed or filling component 105 which bears against the innercircumference of the drum 102 is arranged at a mass-feed or fillingposition. The filling component 105 in this case comprises a connectionpiece 106 for an extruder or some other form of pumping/mixing devicefor supplying a pounded (meat) mass under pressure to a chamber 107which is delimited by walls and has an opening along the inside of thedrum 102. The walls of the chamber 107, at their edges which adjoin thedrum 102, are provided with suitable sealing means 108, thus preventingmeat mass from leaking out of the chamber 107.

It can also be seen in FIG. 1 that at least at the location of thefilling component 105 the openings of the mould cavities 104 are notclosed off on the outside of the drum 2. As a result, meat mass which isalready present in the mould cavities 104 is pushed outwards, so that anoutwardly projecting column of meat mass with a cross section whichsubstantially corresponds to the cross section of the mould cavity 104is formed at each mould cavity 104. Separating means, which separate aslice from the projecting column, preferably along the surface of thedrum 102, are active at a removal position in the vicinity of theunderside of the drum 102, above a moving belt 109 or some otherconveyor mechanism for discharging the moulded products. In thisexample, a taut cutting wire 110 is arranged in a stationary positionalong the underside of the drum 102, which wire cuts off the mouldedproduct “p”, which then falls onto the belt 109. When this takes place,meat mass remains behind in the mould cavity 104, which meat mass is cutoff when it moves past the cutting wire 110 one or more times. In avariant, there may be provision for the separating means to comprise anactuable separating component arranged on the outside of the drum 102for each mould cavity 104, in order to cut off the outwardly projectingcolumn of meat. This is diagrammatically indicated at 111 in FIG. 1.

Furthermore, there may be provision for one or more stations 112 to bearranged along the outside of the drum 102 for the purpose of treatingthe outer surface of the meat mass which is present in the mouldcavities 104, for example for applying an additive to the said surface,for example breadcrumbs, a colorant or flavouring, etc. This operationcould also, for example, involve applying a certain pattern to the meatmass.

There may also be provision for one or more stations 113 to be arrangedin the interior of the hollow drum 102 for the purpose of treating theinner surface of the meat mass which is present in the mould cavities104, for example for applying a layer which prevents or reduces adhesionto the meat mass which is subsequently to be placed into the mouldcavity 104, so that the product “p” may come free from the meat masswhich remains behind in the mould cavity at the removal position withoutthe use of separating means. By way of example, a breadcrumb materialcould applied for this purpose.

FIG. 2 shows a variant on FIG. 1, and components which correspond to thecomponents shown in FIG. 1 are denoted by the same reference numerals;for a description of how they operate, reference is made to thepreceding text.

In FIG. 2, there is provision for a fixing pressure to be exerted on themeat in the mould cavities 104, and this is achieved by closing themould cavities on one side by means of a closure component 114, which inthis case bears against the outer circumference of the drum 102, andexerting a controllable fixing pressure on the meat mass in the mouldcavity from the other side.

In this example, the chamber 107 of the filling component 105 is dividedinto two chambers 107 a, 107 b, each with an associated connection piece106 a, 106 b, for example for an extruder belonging to each of theconnections. The closure member 114 is arranged opposite the chamber 107a, on the outside so that a fixing pressure which provides the meatmaterial with the desired cohesion can be generated in the chamber 107a. Then, in the chamber 107 b, where the meat is subjected to a fillingpressure which is lower than the fixing pressure, further meat materialis pressed into the mould cavity 104, which is then open again on theoutside. Given a suitable arrangement, only meat material which has beensubjected to the fixing pressure and compressed is then separated at theseparating position.

It will be clear that the closure member 114 may, as an alternative tothe stationary plate shown here, also be a moving belt, as will bedescribed below, and may also bear against a larger part of the drum,the same also applying to the chamber 107 a. If appropriate, masses ofdifferent composition may be fed to the chambers 107 a and 107 b,resulting in a layered structure of the product p.

FIG. 3 shows a moulding device 120 with a drum 122 which can rotateabout a substantially horizontal axis and is driven in the direction ofarrow B by drive means (not shown). A filling component 125 with a wallwhich, together with the inner wall of the drum 122, delimits a chamber127 to which a (meat) mass is fed in a manner not indicated, for exampleby means of an extruder, is located in a stationary position in the drum122. The drum 122 is provided with continuous passages 124 which aredistributed over the circumference and extend through the wall of thedrum 122. A slideable moulding component 128 is arranged on the outsideof the drum 122 for each passage 124. Each slideable moulding component128 has a mould holder 129 which is arranged on the drum 122 andcontains an opening for a sliding mould 130 which can be slid to andfro. In the retracted position of a mould 130, (meat) mass can beintroduced into the mould 130 via the associated passage 124 when itmoves past the filling component 125. Then, the mould 130 can be slidout of the associated holder 129, an operation which in this case iscarried out by means of curved track 131, against which the moulds 130bear under springloading or the like.

When the mould 130 has been sufficiently extended in the removalposition at the bottom of the drum 122, the moulded product p falls outof the mould 130 onto the discharge belt 133. If appropriate, removal ofthe product p from the mould 130 can be assisted by means of compressedair or some other ejector means.

It will be clear that the filling component 125 may also be positionedalong the outer circumference of the drum 122, with the sliding moulds128 on the inside of the drum 122.

FIG. 4 shows a fourth exemplary embodiment of a moulding device 1according to the invention for moulding three-dimensional products froma mass of foodstuff which is suitable for human consumption, inparticular a mass which predominantly consists of pounded (chicken)meat. The moulding device 1 is of the “rotating drum” type and comprisesa rotatable drum 2 which, in a stationary frame (not shown), is mountedin such a manner that it can rotate about an axis of rotation 3, whichin this case is substantially horizontal. The drum 2 is driven,preferably at a substantially constant rotational speed, in a directionof rotation which is indicated by arrow A, by drive means (not shown).

The drum 2 has a substantially cylindrical drum wall with a diameterwhich is, for example, between 0.15 and 0.7 meter and a length which is,for example, between 0.3 and 2 meters. The considerable length of a drum2 of this nature is possible in particular because of the tubular shapeof the drum 2, which tubular shape is very stable with respect to theforces which are generated during the moulding process. These forces,which are generated in particular by the filling pressure with which themass is pressed into the mould cavities and the fixing pressure, inprincipal cause the drum 2 to bend, which causes problems in particularfor seals which bear against the inside and/or outside.

Preferably, the drum 2 is formed from a metal tube which is commerciallyavailable as standard, but it will be clear that the drum 2 may also beassembled from sections or, for example, from a special casting. Thedrum may also be provided with internal reinforcements, for examplereinforcement plates which are located at axial distances from oneanother.

The drum 2 may also be formed by a plurality of tubes which slide intoone another, which structure is advantageous for the arrangement ofconnecting passages, in particular for compressed air and/or vacuum,which lead to the mould cavities 4. These passages could then bearranged substantially as grooves in the walls of the said tubes.

The bending can be reduced by providing the drum 2 with prestressingmeans which generate an axial prestress in the drum wall and thus reduceany bending. The bending can also be reduced by making use of one ormore robust support rollers which bear against the drum wall, forexample in the interior of the drum opposite the filling device 5, inorder in this way to absorb the forces which the filling pressure exertson the drum 2.

The drum 2 is provided with a plurality of mould cavities 4 which aredistributed over the outer circumference and are open on the outercircumference of the drum 2. By way of example, the mould cavities 4 arearranged in a pattern with a plurality of circumferential rings, locatednext to one another in the longitudinal direction of the drum 2, ofsimilar mould cavities. There may also be provision for the mouldcavities in each ring to be distributed at equal angular intervalsaround the circumference of the drum, in which case the mould cavitiesof adjacent rings are always offset in the circumferential direction.Such an arrangement of the mould cavities leads to mould cavities beingfilled virtually continuously, instead of groups of mould cavities beingfilled simultaneously, with a time gap between filling operations. Thismanner of continuous filling, particularly with a continuous supply ofmass to the filling component, for example by an extruder, leads to auniform filling pressure. This arrangement will also deliver acontinuous stream of moulded products.

Obviously, it is also conceivable for mould cavities 4 of differentshapes to be arranged on the drum 2. In this case, the mould cavitiesmay be of any conceivable form, for example circular or rectangular, butalso in novelty shapes, such as in the shape of a Christmas tree, acrescent, a star, a triangle, etc. In an advantageous embodiment, one ormore mould cavities may form part of a removable mould which can bereleasably attached to the drum. This may, for example, be achieved byproviding the drum 2 with a large number of identical holding featuresaround its outer circumference, for example openings arranged in thedrum wall and/or coupling means positioned on the outer circumference, amould fitting into each holding facility, in which case a large numberof moulds belong to the moulding machine and are identical insofar asthey can be positioned on the drum by means of the holding facilities,but have mould cavities of different designs.

If different mould cavities 4 are arranged on the drum 2, it ispossible, by selecting a suitable arrangement of the said mould cavities4, to ensure that the differently shaped products do not have to behandled, or scarcely have to be handled, during subsequent processing.For example, it is conceivable to produce sets of three products ofdifferent shapes and to supply these sets in a single pack. In thiscase, it may be advantageous for the three different mould cavities tobe arranged next to or immediately after one another on the drum, sothat the products are delivered by the moulding device in sets of three.

As an alternative to the drum, it is also possible, albeit with a higherlevel of technical complexity, to provide for the moulds, each with oneor more mould cavities therein, to be arranged on a common turret whichdefines a loop-like movement path for the moulds, in which case drivemeans are provided, which move the moulds along the movement path.Preferably, in this case, the drive means move the moulds at asubstantially constant speed along the movement path. The loop-likemovement path may in this case be a circle, as with the drum, but otherforms are also easy to achieve in practice, such as for example a pathwith two straight sections which are connected at their ends via 180°bends.

To feed a portion of meat mass to the mould cavities 4, a stationarymass-feed or filling component 5, which bears against the outercircumference of the drum 2, is arranged in a mass-feed or fillingposition, in this case in the vicinity of the top side of the drum 2.The filling component 5 in this case comprises a connection piece 6 foran extruder or some other form of pump device for supplying the meatmass under pressure to a chamber 7 which is delimited by walls and hasan opening on the side of the drum 2. At their edges which adjoin thedrum 2, the walls of the chamber 7 are provided with suitable sealingmeans 8, making it possible to prevent meat mass from leaking out of thechamber 7. The filling component 5 shown is in fact intended tocompletely fill the mould cavity. In another embodiment (not shown), thefilling component may also be designed to feed a predetermined portionto the mould cavity, for example on the basis of the volume and/or massof the portion, the volume of which portion may therefore be smallerthan the volume available in the mould cavity. For example, a fillingcomponent of this nature moves a slice or other preformed shape of thefoodstuff which is to be processed into the mould cavity.

It can also be seen from FIG. 4 that the moulded products “p” areremoved from the mould cavities 4 at a removal position, in this case inthe vicinity of the underside of the drum 2, above a conveyor belt 9 orother conveyor mechanism for discharging the moulded products. Thisejection may be effected by the force of gravity, as illustrated in FIG.4, but owing to the adhesion of the meat mass to the walls of the mouldcavities 4, the removal is preferably facilitated or assisted in wayswhich are to be described in more detail below.

The filling component 5 ensures that a portion of the meat mass is movedinto a mould cavity 4 at a defined filling pressure. To obtain firmcohesion between the pieces of meat, so that ultimately a stable productis obtained, it is necessary, after the mould cavity 4 has been filled,to exert a fixing pressure on the meat mass for a defined period. Forthis purpose, there is provision for the filling openings, which arelocated on the outside, of the mould cavities 4 to be closed off over atleast part of the path between the filling component 5 and the removalposition, preferably over virtually the entire path.

In this case, the mould cavities 4 are closed off with the aid of aflexible belt 10 which, in the path in question, bears against the outercircumference of the drum 2 and preferably moves with the drum 2. Thebelt 10 runs around a top roller 11, which is arranged in the vicinityof the filling component 5 or even, with the belt 10 wrapped around it,forms part of the walls of the chamber 7 of the filling component 5. Inthe vicinity of the removal position, the belt 10 runs around a bottomroller 12 and also runs around a tensioning roller 13 which supports thereturn section of the belt 10. If appropriate, a separate drive for thebelt 10 may be provided. It is also possible to provide cleaning meanswhich clean the belt 10 in its return section.

Closing the mould cavities 4 with the aid of the belt 10 bearing againstthe drum 2 ensures that the meat mass in the mould cavities 4 is placedand held under a fixing pressure, with the result that the desiredcohesion and mutual adhesion of the (meat) pieces is obtained. In theembodiment shown in FIG. 4, the fixing pressure is obtained by the factthat the convex side of the mass which is produced at the fillingcomponent 5, is, as it were, pressed flat into a mould cavity 4 by thebelt 10, with the result that the mass is placed and held under a fixingpressure in the closed mould cavity 4 throughout the time during whichthe belt 10 closes off the mould cavity 4.

The device shown in FIG. 4 also allows the outside of the mouldedproduct to be treated, in particular along the path between the locationwhere the outside is no longer covered by the belt 10 and the moment atwhich the product is ejected. For example, a spraying device could beused to apply a layer to the product. As soon as the product rests onthe discharge belt, the other side could also be treated.

FIG. 5 shows a fifth exemplary embodiment of a moulding device accordingto the invention. Where components correspond to the components shown inan embodiment described above, these components are denoted by the samereference numerals; reference is made to the preceding text for adescription of how they function.

In FIG. 5, reference 15 denotes a film-feed mechanism for feeding film.This preferably thin, flexible (plastic) film 17 is placed against theoutside of the drum 2 at a film-placing position 16, which is upstreamof the filling component 5, as seen in the direction of rotation, andserves to ensure that at least the walls and the base of the mouldcavities 4 are covered by the film 17.

To ensure that the amount of film 17 present at each mould cavity 4 ofthe device is such that this film 17 is able to bear taut against thebase and the side wall of the mould cavity 4 when the meat mass isintroduced into the mould cavity 4, vacuum means are provided here,which, between the film-placing position 16 and the filling component 5,remove air from the mould cavity 4 which is covered by film 17. Thevacuum means in this case comprise a tray 18 which is arranged in astationary position in the rotating drum 2 and is formed by a wall whichin part lies at a distance from the inside of the drum and at its edgesbears in a sealed manner against the inside of the drum 2, so that aclosed space which is delimited by the wall of the tray 18 and theinside of the drum 2 is formed. This closed space is connected to avacuum pump or the like, so that a reduced pressure can be generated inthe tray 18. Furthermore, the drum 2 is provided at each mould cavity 4with a connecting passage 19 which connects the mould cavity 4 to theinside of the drum 2, so that at the moment at which a mould cavity 4reaches the tray 18 air is sucked out of the mould cavity 4 via theassociated passage 19, while the opening of the mould cavity is alreadycovered by the film 17 on the outside of the drum 2. Partly because ofthe appropriate flexibility of the film 17, the film 17 matches theshape of the mould cavity 4. In this example, this suction on the film17 is maintained until the filling component 5 fills or has filled themould cavity 4.

The film 17 prevents the meat mass from sticking to the drum 2, which isparticularly relevant for removal of the moulded product and alsoprevents contamination to the drum 2. Furthermore, the film 17 can beused to eject the moulded product from the mould cavity 4, for exampleby exerting a pulling force on the film 17 in the vicinity of theremoval position, an operation which can be achieved, for example, by(temporarily) rapidly rotating a pulling roller 20 against which thefilm 17 bears, thus exerting tension on the film 17.

If the product p sticks to the film 17, it is preferable to guide thefilm 17 through a sharp bend, for example around bar 20 b, so that thefilm 17 moves into a position in which it is approximately at rightangles to the surface of the product and is thus stripped off from thesurface of the product.

The passages 19 may also be used to eject the moulded product byintroducing compressed air into the mould cavity 4 beneath the film 17via the said passages 19 at the removal position. This may be effectedusing excess-pressure tray 22, which is positioned in the drum 2 in thevicinity of the removal position. The tray 22 is arranged in astationary position and bears in a sealed manner against the inside ofthe drum 2, and is connected to a compressor (not shown) for feedingpressurized air (or another gas) to the tray 22, with the result thatthe product and the film 17 are pressed out of the mould cavity 4. Ifappropriate, there may be provision for the tray 22, as seen in thedirection of rotation of the drum 2, to be divided into a plurality ofcompartments 22 a, 22 b by means of one or more partitions 21, in whichcase the gas pressure can be adjusted separately in each compartment 22a, 22 b. This makes it possible to successfully control the ejection ofthe moulded product. Incidentally, the same measure may also be used forthe reduced-pressure or suction tray 18.

In a variant which is not shown, there may be provision for a medium tobe pressurized in the mould cavities 4 via the passages 19 in the pathin which the mould cavities 4 are closed off on the outside by the belt10. This may, for example, be achieved by arranging anexcessive-pressure tray, corresponding to tray 22, which is divided intoone or more compartments at that location but on the inside of the drum2. Then, by suitably regulating the pressure of the medium, it ispossible to control the fixing pressure in the mould cavities 4. Themould cavities 4 may, for example, be designed in the manner which willbe explained in more detail below with reference to FIGS. 11, 12 a and12 b.

The film 17 is, for example, disposable and is guided onto a reel andwound up after it has run around the drum, after which a reel of used,dirty film is removed and destroyed. However, the film 17 could also beused for packaging the product.

FIG. 5 also shows a station 25 which is arranged along the outside ofthe drum 2, between the film-placing position 16 and the fillingcomponent 5. The station 25 may, for example, be used to apply a coatingor the like to the film 17. This coating may be in a wide variety offorms, for example may be a liquid substance which influences theadhesion between the meat and the film 17, or an edible coating which isintended to influence the appearance of the outer layer of the mouldedproduct, for example a coating containing breadcrumbs and an egg-whiteemulsion, a colorant or flavouring etc. The station 25 may compriseliquid sprayers and/or atomizers, which only operate when a mould cavity4 covered by film 17 moves past, and/or a fan or other blowing devicefor blowing more or less solid edible particles, for example edibleflakes, onto the film, which may previously have been moistened.

In a variant on the device 1 described above, the reduced pressureacting on the film 17 is eliminated after it has been sucked undervacuum into the mould cavity 4, before the filling device 5 is reached,so that the film 17 is again approximately in the plane of the openingof the mould cavity 4. The aim of this is to ensure that the meat massbears against the film 17 without the inclusion of air in the vicinityof the filling device 5 and moves into the mould cavity 4 together withthe film, during which operation, if appropriate, reduced pressure isagain exerted via passage 19. This procedure can be achieved byproviding the tray 18 with the partitions 18 a, 18 b as shown in FIG. 5.

It should be noted that the step of firstly sucking the film 17 into themould cavity 4 before the filling device 5 is reached is important inorder to ensure that sufficient film material collects at the locationof the mould cavity 4. If the film 17 were to be in a taut positionabove the opening of the mould cavity 4 when the mould cavity is beingfilled, it is impossible, or virtually impossible, to feed film materialwhen the meat mass is pressed into the mould cavity 4, so that a veryhigh level of elasticity of the film 17 would be necessary in certainareas, in particular around the edge of the mould cavity 4.

To avoid air being enclosed between the film 17 and the meat mass, usecould also be made of steam or another condensable gas. In that case, asteam tray, for example, would be placed against the outside of thedrum, immediately upstream of the filling component 5. Consequently,steam will be included between the film and the meat mass, but thissteam will rapidly condense to form a minimal quantity of water.

As an alternative, it is possible for the belt 9 to be covered with afilm which moves with it and onto which the products fall. This filmcould then, for example, form part of the packaging for the products.

FIG. 6 shows a variant on the device shown in FIG. 5, in which theprincipal change is that the device is positioned upside-down.Consequently, the filling component 5 is now located in the vicinity ofthe underside of the drum 2. A second web of film 17 b is fed to the topside and is guided over the drum 2, so that the moulded products, whichare still enclosed in the mould cavities 4, are enclosed between the twofilms 17 and 17 b.

In this example, a film-welding device 23 is also arranged in thevicinity of the top side of the drum 2, which film-welding device weldsthe two layers of film 17, 17 b together, for example around each cavity4, so that the product is packaged in film while it is still inside themould cavity. If appropriate, the film layers 17, 17 b are cut or meltedthrough around the outside of the weld, so that the product enclosed infilm is detached from the two layers of film. The product which ispackaged in film is then discharged by means of the excess-pressure tray22 or some other removal mechanism. Obviously, it is conceivable thatthe product will be enclosed between the two film webs 17, 17 b only ata later stage, after the products lying on the film 17 have been removedfrom the mould cavities 4 of the device. The separation of the productswhich are packaged in film from the film webs may also take place at alater stage, so that the film webs can still be used as a mechanism forconveying the packaged products. One advantage of the device shown inFIG. 6 is the height at which the products are removed, which makes iteasy to provide connection to subsequent stations.

FIG. 7 shows a seventh exemplary embodiment of a moulding deviceaccording to the invention. Where components correspond to thecomponents shown in an embodiment which has been described above, thesecomponents are denoted by the same reference numerals; reference is madeto the preceding text for an explanation of how they function.

In FIG. 7, there is provision for a film 30 to be placed between thebelt 10 and the drum 2, which film 30 moves with the drum 2 and the belt10. This measure allows the film 30 and the belt 10 each to havedifferent properties which are adapted to their specific tasks. Inparticular, the film 30 in this case serves as a protection forprotecting the belt 10 from the (meat) mass in the mould cavities 4, sothat the belt 10 does not come into contact with the (meat) mass and istherefore not contaminated and also does not have to be cleaned.

In this example, the film 30 is intended for single use and is suppliedfrom a supply reel 31 and then runs around the top deflector roller 11of the belt 10 via guide roller 32. In this example, the film 30 alsoruns around the bottom deflector roller 12 of the belt 10 and is thenseparated from the return section of the belt 10 via guide roller 33 andis wound onto a discharge reel 34. However, it is also possible for thefilm 30 to remain in position against the products when the mouldedproducts are ejected and to be used to discharge the products, and ifappropriate even for handling the moulded products in further processingdevices and/or for packaging the products.

For example, it is possible for the conveyor 9 to be provided withopenings in its belt and for a reduced-pressure tray 35 to be positionedbeneath the belt 9 in the vicinity of the ejection position of theproducts, so that the film 30 can be sucked onto the belt 9 and can bemoved with the belt 9. In this case, the products continue to lie on thefilm 30. This has the advantages that the conveyor 9 is notcontaminated, that the moulded product is supported when it is ejectedfrom the drum, and that the position of the product on the film 30 isfixed, which may be advantageous for any subsequent processingoperations.

In a variant which is not shown, the film 30 is also designed as anendless loop, i.e. in the same way as the belt 10, in which case, forexample, there is provision for the film 30 to be cleaned. Incidentally,in these illustrations, the film is always shown and described as beingconsiderably thinner than the belt, although it is equally conceivablefor the components described as film and belt to be of similarthickness.

FIG. 7 also shows the station 25 with which, for example, the mouldcavities 4 can be cleaned before they are refilled. If appropriate, anon-stick agent may also be arranged in the mould cavities 4, or someother means may be provided, such as that illustrated in FIG. 5.Obviously, the devices shown in FIGS. 5, 6 and 7 can also be combined toform a single device, in which the portions of meat mass in the mouldcavity 4 are completely surrounded by the two films 17 and 30.

In a further variant, the discharge belt 9 with the tray 35 bearsagainst the drum 2 and the belt 9 is moved at the same speed. As aresult, the product is, as it were, sucked firmly onto the belt 9 whileit is still in the mould cavity 4, and then the product is graduallyremoved from the mould cavity.

FIG. 8 shows an eighth exemplary embodiment of a moulding deviceaccording to the invention. Where components correspond to thecomponents shown in an embodiment which has been described above, thesecomponents are denoted by the same reference numerals; reference is madeto the preceding text for a description of how they function.

In FIG. 8, instead of the disposable film 17 as described with referenceto FIG. 5, a belt 40 of elastically deformable (plastic) material isused, which belt bears against the outer circumference of the drum 2from a placing position 41 upstream of the filling component 5 to thearea of the removal position of the products, on the underside of thedrum 2. The belt 40 is used, inter alia, to cover the base and the sidewalls of the cavities 4, so that these parts do not come into directcontact with the (meat) mass.

To enable the belt 40 to be moved into the mould cavities 4, thereduced-pressure tray 18 is again provided, as are the associatedconnecting passages 19 in the drum wall leading to the mould cavities 4.By applying reduced pressure, the belt 40 can thus be deformed so thatit bears against the delimiting walls of the mould cavities 4.

Preferably, the belt 40 is of an elastic quality which is such that itrestores its shape, i.e. the belt 40 is preferably designed in such away that it returns to its original planar form when no external force,such as the vacuum, is being exerted thereon; this can be clearly seenin FIG. 8.

Preferably, the belt 40 is cleaned in the section in which this belt 40is clear of the drum 2.

Due to the shape-restoring properties of the belt 40, it is preferablefor the reduced pressure generated by the tray 18 also to act while themould cavities 4 are being filled. The shape-restoring property of thebelt 40 can also be utilized when the shaped product is being removedfrom the mould cavity 4, if appropriate with the assistance of a tensileforce being exerted on the belt 40, which force pulls the belt 40 backinto a flat state in this position. Furthermore the removal of theproduct from the mould cavity 4 can be assisted by pressing air betweenthe belt 40 and the drum 2 via excess-pressure tray 22.

The belt 40 can also be used to control the fixing pressure in the mouldcavities 4 in the path between the filling component 5 and the ejectionposition. For example, the reduced pressure between the belt 40 and thedrum 2 can be partially or completely eliminated in that path; it iseven possible to produce an excess pressure, for example by means of thetray 43, which is of similar design to the trays 18 and 22 and may bedivided into a plurality of compartments with separately adjustablepressures by means of partitions.

As an alternative to the trays 18, 22 and 43 shown in FIG. 8, it is alsopossible for the connecting passages 19 which lead to the mould cavities4 and connect these mould cavities 4 to an excess-pressure source or areduced-pressure source or atmosphere as desired to be designed in adifferent way. By way of example, these connecting passages 19 may becoupled via rotatable couplings to excess-pressure and/orreduced-pressure pipes or vent pipes which are positioned on the axis ofrotation of the drum 2. The connecting passages 19 could also lead, inor along the drum wall, to one or both ends of the drum, where theycould be connected to stationary lines leading to the abovementionedsources or to atmosphere, as is known, for example, from U.S. Pat. No.4,212,609.

It will be clear that a combination of the devices shown in FIGS. 8 and7 is possible, as is a combination of the devices shown in FIGS. 8 and5, thus preventing contamination of the belt 40.

At the location of the ejector tray 22, the discharge belt 9 runs pastthe drum 2 at a short distance therefrom, so that the product comes intocontact with the belt 9 while it is still largely inside the mouldcavity 4. In this case, the belt 9 is driven at the same speed as thedrum 2. The downstream section of the belt 40 gradually runs away fromthe discharge belt 9, so that the product p is released from the belt 40and stands on the belt 9. At the end of this section of belt 40 there isa roller 50 of small diameter, so that the belt 40 runs through an acuteangle and is thus pulled off the product p.

Depending on the composition of the mass which is to be moulded, it willalso be possible to use the device shown in FIG. 8 without the presenceof the belt 40 or a film with similar function, as explained withreference to FIG. 5. In order, in such a case, to make it possible torealise the fixing pressure by means of gas pressure and/or to eject themoulded product, it is possible to provide for the base of the mouldcavity to be covered with a “sealed” layer by means of a suitable feedapparatus upstream of the filling component. This layer could, forexample, be a disc of solid material, for example paper or an ediblematerial such as a pastry product, but could also, for example, comprisea liquid which sets, for example fat, which is then introduced into themould cavity and solidifies to form an impenetrable layer. Thus, thislayer in fact functions as a “plunger” in the mould cavity.

When ejecting the product from the mould cavity, it may be advantageousto cool the product on the outside, for example by carrying out theejecting operation using gaseous nitrogen. The cooling leads, interalia, to shrinkage of the product, and consequently it will often comeout of the mould cavity more easily.

The main concept of the invention will now be explained in more detailwith reference to the device shown in FIG. 8, which concept relates tothe control of the important technological perimeters associated withthe moulding process.

By means of the filling component 5, a mould cavity 4 is completelyfilled with the (meat) mass which is fed to the filling component 5, forexample via an extruder or a pump. In the process, the mass is subjectedto a filling pressure, so that the mass flows into the mould cavity 4.The mould cavity 4 is preferably filled using a filling pressure whichis uniform over time and is preferably low. If appropriate, additionalfilling-pressure control means may be provided, which seek to keep thepressure in the chamber of the filling component at a virtually constantlevel.

When the mould cavity 4 is full, the mass contained therein is stillsubject to the filling pressure, the duration of which is dependent onthe speed of the drum 2 and the length of the opening of the fillingcomponent 5, measured in the circumferential direction. If appropriate,this length is adjustable in order to be able to regulate the fillingperiod.

After filling, the mould cavity 4 is closed off by means of the belt 10,which belt 10 extends over part of the circumference of the drum 2. Thecombination of the length of that part of the circumference and therotational speed of the drum leads to a maximum duration of the fixingperiod during which the mould cavities are closed off and a fixingpressure can be exerted on the mass contained therein. By thenintroducing pressurized gas or liquid beneath the belt 40 via theconnecting passages 19, the mass which is present in the closed mouldcavities 4 is subjected to a fixing pressure, so that the pieces whichform the mass adhere to one another. In the device shown in FIG. 8, theactual duration of the fixing period may, for example, be set byseparately regulating the feed of gas or liquid to each of thecompartments of the tray 43; thus, it is conceivable, for example, foras yet no pressurized liquid or gas to be fed to that compartment of thetray 43 which is located immediately downstream of the tray 18.

In a variant which is not shown, the device allows the length over whichthe belt 10 covers the drum to be adjusted, for example by moving therollers 12 and 13, so that in this way too it is possible to adjust theduration of the fixing period without having any effect on the durationof the filling period.

It will be clear that the device shown can be used to manipulate thefilling pressure and fixing pressure, as well as the duration of thefilling period and of the fixing period, and furthermore also thetransition from the filling period to the fixing period as desired, inorder to obtain an optimum result for the mass which is to be processed.

FIGS. 8 a-d show four possible variants for the filling-pressure curveover time, and FIGS. 8 e-g show three possible variants for the profileof the fixing pressure over time, it being clear that in the actualprocess the fixing pressure follows the filling pressure which haspreviously been exerted and in principle any desired combination ispossible. It should be noted that the profiles shown are only examplesand that the process can be adjusted optimally for each mass, forexample on the basis of tests carried out using the mass which is to beprocessed.

In FIG. 8 a, the filling pressure is completely eliminated after themould cavity has been filled; this may, for example, be achieved bybringing the filling opening of the mould cavity into contact with theatmosphere.

In FIG. 8 b, the filling pressure is maintained for a longer time thanin FIG. 8 a, for example by extending the distance over which the movingmould cavity is moving past the filling component or by lowering thespeed at which it moves past. The filling pressure then falls toatmospheric pressure.

In FIG. 8 c, the filling pressure is maintained without falling toatmospheric pressure, after which a higher fixing pressure can beexerted on the mass.

In FIG. 8 d, the filling pressure falls slightly at the end of thefilling period, but not to atmospheric pressure.

In FIG. 8 e, the fixing pressure is only maintained for a short fixingtime. In this case, the fixing pressure will usually be higher than thefilling pressure which has previously been exerted.

In FIG. 8 f, the fixing pressure is maintained for a longer time. Inthis case too, the fixing pressure will usually be higher than thefilling pressure, but since both the duration of the fixing period andthe fixing pressure are parameters, it is also conceivable for thefixing pressure, for example temporarily, to be lower than the fillingpressure.

FIG. 8 g shows how the fixing pressure can be varied during the fixingperiod, for example can be reduced in steps. To avoid the possibility ofthe mass which is still under pressure expanding when the mould cavityis opened, directly at the location where the opening forms, it may beadvantageous to reduce the fixing pressure in the final phase of thefixing period to atmospheric pressure or even to below this pressure.

It will be clear that the fixing pressure may also have an entirelydifferent profile, for example may initially rise and then fall again.

FIG. 9 shows a ninth exemplary embodiment of a moulding device accordingto the invention. Where components correspond to the components inaccordance with an embodiment which has been described above, thesecomponents are denoted by the same reference numerals; reference is madeto the preceding text for an explanation of how they function.

In FIG. 9, the fixing pressure is regulated in the path between thefilling component 5 and the removal position by regulating the pressurewith which the belt 10 is pressed against the meat portions accommodatedin the mould cavities 4. To this end, a controllable pressure, forexample an air pressure or a liquid pressure, is preferably exerted onthat side of that part of the belt 10 which bears against the drum 2which is remote from the drum 2. In this case, this is achieved byplacing a closed tray 51 against the belt on that side, which tray formsa chamber 52, one side of which is delimited by the belt 10. Byconnecting the tray 51 to a suitable source of pressurized medium, forexample an air compressor, the pressure in the space formed by the tray51 and the belt 10 can be adjusted, and thus the pressure with which thebelt 10 presses against the portions of meat in the mould cavities 4 canbe regulated.

Obviously, it is conceivable to divide the tray 51, by means of one ormore partitions, into compartments which preferably form pressurecompartments which lie one behind the other in the direction of rotationof the drum 2, so that different fixing pressures can be implemented atdifferent moments during the fixing period of the product.

It will be clear that the measure in accordance with FIG. 9 can becombined with preceding exemplary embodiments.

The belt 10 may be provided with a profile on the outside, in such amanner that this profile forms a complementary pattern on the outside ofthe products, for example a studded, ribbed or grid profile.

In order to provide the outside of the product with the appearance ofhaving been grilled on a grate, it is also possible to provide a heatedstamp with a suitable pattern along the drum 2, which stamp is pressedagainst the products which are still enclosed in the mould cavities 4.Obviously, this feature can also be provided in the device shown in FIG.8.

FIG. 10 shows a tenth exemplary embodiment of a moulding deviceaccording to the invention. Where components correspond to thecomponents shown in an embodiment described above, these components aredenoted by the same reference numerals; reference is made to thepreceding text for an explanation of how they function.

In FIG. 10, the bases of the mould cavities 4 are designed in the formof a flexible membrane, which in this case is achieved by designing themould cavities 4 as openings which run all the way through the wall ofthe drum 2 and by covering the inside of the drum wall with acylindrical membrane 60. At the filling component 5, an excesshydrostatic pressure is exerted on the inside of the membrane 60, insuch a manner that the membranes 60 yields outwards and projectspartially into the mould cavity 4. In this case, the excess pressure isproduced using an excess-pressure tray 62. The filling component 5 thenintroduces a portion of meat into the mould cavity 4, this portion infact being smaller than the actual volume of the mould cavity.

After the mould cavities 4 have been filled, i.e. downstream of thefilling component 5, the excess pressure on the inside of the membrane60 is eliminated and, if appropriate, a reduced pressure is generatedusing reduced-pressure tray 63. As a result, the base of the mouldcavity 4 moves inwards. This inwardly directed movement of the base ofthe mould cavity 4 is intended to compensate for the expansion of theportion of meat, which expansion occurs as soon as pressure is no longerbeing exerted on the portion of meat on the outside of the drum 2. Theelasticity of the meat mass, which is partially caused by the air whichis present in the meat mass, would otherwise lead to the meat moving outof the mould cavity 4 on the outside and forming a “head” which projectsoutside the circumference of the drum 2. By moving the base inwards,this expansion is able to take place without the said head being formed,and it is possible that a hollow may even form in the outside of theportion of meat in the mould cavity 4. The absence of the head preventsthe said head from being spread out as a result of coming into contactwith the belt 10, which would result in the loss of meat material andrapid contamination of the moulding machine. If appropriate, the base ofthe mould cavity is not moved outwards before the mould cavity isfilled, and the above-described compensation for the expansion of themass takes place entirely by moving the base inwards.

As soon as the belt 10 lies over the outer opening of the mould cavity4, the fixing pressure can be generated in the mould cavity, which isthen closed on all sides. This may, for example, be achieved by exertingan excess pressure on the inside of the membrane 60 with the aid ofexcess-pressure tray 64. Also, if appropriate in combination with theabove, an excess pressure could be exerted on the outside of the belt10, as described with reference to FIG. 5. Excess-pressure tray 65 couldassist with ejection of the product.

It will be clear that the concept described with reference to FIG. 10 ofmoving the base of the mould cavity into an outer position prior to orduring filling of the mould cavity and then moving it into an innerposition after the mould cavity has been filled and before the belt or afixed closure member which bears against the outside of the drum isreached, closing off the mould cavity on that side, can also beimplemented in moulding machines with a mould-cavity base which isinherently rigid and can be moved by appropriate displacement means.This inwards movement prevents a head of meat mass projecting from theuncovered outer side of the mould cavity and being spread out by contactwith the closure component. After the mould cavity has been covered bythe closure component, the base of the mould cavity can be movedoutwards again, if appropriate in order to produce the desired fixingpressure by means of the position of the base. Furthermore, it will beclear that this concept can be applied to all types of moulding machineswith mould cavities which move past a filling component, i.e. not onlyrotating drum type machines but also slide plate machines and turretmachines.

FIG. 11 shows a cross section through part of a moulding machine, therest of which is not shown, for example one of the above-describedmoulding machine of the rotating drum type, for moulding athree-dimensionally moulded product from a mass of foodstuff which issuitable for human consumption, in particular from a mass which consistssubstantially of pounded (chicken) meat. The part which is shown relatesto a drum 2 and a mould 150 which is fixed therein by means of bolts orother attachment means and is made, for example, from metal or rigidplastic, with a mould cavity 151 therein. The mould cavity 151 isdelimited by a base 152 and a circumferential wall 153 and is open onthe side lying opposite the base 152. A first passage 154, which is incommunication with one or more first nozzles 155 located in the centralarea of the base 152, is associated with the mould 150. Furthermore,there is a second passage 160 which is in communication with one or moresecond nozzles 161 in the base 152. These second nozzles 161 lie in anannular area between the central area of the base, which is providedwith the first nozzles, and the circumferential wall 153, or ifappropriate even in the circumferential wall 153, in the vicinity of thebase 152. The passages 154 and 161 can be selectively connected to asource of air or another gas under pressure or to a vacuum pump oranother reduced-pressure source.

To prevent contamination of the mould 150 and to avoid adhesion betweenthe meat mass and the mould 150, there is provision for a flexiblemembrane 165 to be arranged between the walls of the mould cavity andthe portion of meat 166 which is to be introduced into the mould cavity151. In this figure, the thickness of the membrane 165 is exaggerated,and the membrane may, for example, be formed by a disposable film or bythe elastic belt as described above. If appropriate, the membrane 165may form part of the mould 150 and may be fixed to the mould 150 in thevicinity of the circumferential edge of the filling opening of the mouldcavity 151.

If the membrane 165 is a film as described, for example, with referenceto FIG. 5, the air which is present in the mould cavity 151 after thefilm has been placed over the opening of the mould cavity 151 is suckedout via the first and/or second passage 154, 161, so that the film comesto lie taut against walls of the mould cavity 151. Then, if appropriateat the same time as the mould cavity 151 is evacuated, the portion ofmeat is introduced into the mould cavity 151.

The above-described design of the mould 150 is also important forreleasing the moulded meat product from the mould cavity 151. In thiscase, there is provision for a pressurized medium to be fed first to thesecond passage 160 and thus the nozzles 161 in the vicinity of thecircumferential wall 153, while no medium is being fed to the firstnozzle(s) 155, or even a reduced pressure is maintained at the firstnozzle 155. This ensures that the product 166 is firstly pressedoutwards in the area in the vicinity of the circumferential wall of themould cavity 151 while the product in the centre remains in position. Bythen feeding a pressurized medium via the first nozzle(s) 155 as well,the whole of the product 166 is removed from the mould 150 and movesuniformly upwards.

The membrane may also at the same time serve as (part of) the packagingof the moulded product; for example, it is conceivable for the membrane170 from FIG. 12 a to be placed as a loose element inside the mould andto be held in place temporarily, for example via a vacuum groove runningalong the circumferential wall of the mould cavity, and to remain aroundthe product as packaging after the product has been moulded.

The inventive concept explained with reference to FIG. 11 can also berealized with a base/wall covering structure for the mould cavity asshown in FIG. 12 a. In this design, the base 152 and the wall 153 of themould cavity are covered by a covering with a flexible part 170, whichcovers the wall 153 and an annular area of the base 152 which adjoinsthe wall, and a stiffer or even hard part 171, which covers the centralpart of the base 152. By then supplying air via passage 160, the initialmovement takes place in that part of the mass 166 which is located alongthe wall 153. Then, the centre of the said mass 166, which is supportedby the rigid part 171, also moves out of the mould cavity 4. The rigidpart may also be made of the same material as the flexible part 170 butmay then be cooled and therefore be made more rigid, for example bycooling, for example using cold nitrogen.

In a variant, the rigid part 171 of the membrane is absent, and isreplaced by a rigid piece of the edible product which is ultimately tobe produced on the membrane.

The structure shown in FIG. 12 a is particularly advantageous forexerting a fixing pressure on the mass 166, since the said mass 166 iscovered on the side of the opening in the mould cavity by a suitableclosure component. By then exerting air pressure via passage 154, thehard disc part 171 presses against the mass, in fact in the manner of apiston, but without the associated disadvantages.

In a variant shown in FIG. 12 b, the cover comprises flexible film or aflexible membrane 180, and a part of the base 152 of the mould cavitywhich is free of the wall 153 is designed as the end face 180 of amoveable disc-like piston 181. The annular area 182 of the base 152around the piston 181 lies—in the retracted position of the said piston181—further inwards than the end face 180. Nozzles of air passage 184are present in the mould 150, below the piston 181. If the mass 166 iscovered on the side opposite the piston 181 and if it is desired toexert a fixing pressure on the mass 166, air or some other gas or aliquid can be supplied under pressure, via the air passage 184, so thatthe piston 181 is pressed outwards and the mass is placed underpressure. If the product, after the fixing period, is no longer covered,and the moulded product is ejected, pressurized medium can again besupplied via passage 184, with the result that this pressurized mediumemerges from under the piston 181 and initially presses the mass 166outwards in the annular area, followed by the piston 181.

It will be clear that the mould designs described with reference toFIGS. 11 and 12 a, 12 b, 12 c may also be applied to all the known andabovementioned types of (meat) moulding machines, i.e. also in machinesof the slide-plate and turret type.

The abovementioned moulds are all of “self-releasing” design, so that itis not necessary to design the mould in two or more parts which have tobe moved apart in order to remove the moulded product from the mould. Itwill be clear that the inventive concept can also be applied to a mouldwith a mould cavity which is not of “self-releasing” design and, forexample, comprises two mould halves which have to be moved apart inorder for the moulded product to be released. Such moulds may also, forexample, be placed around the circumference of a drum or accommodated ina turret, which will be explained in more detail with reference to FIGS.18 a and 18 b.

FIG. 12 c shows a mould 190 of particular design which can be used toproduce products which are not automatically released. The mould 190comprises two mould halves 191 and 192, of which the mutually facingsides, which between them delimit a mould cavity 196, are at leastpartially defined by the heads of a large number of pins 193 and 194,respectively. The pins 193, 194 can be moved in their longitudinaldirection, so that in this way the shape of the mould cavity 196 can bedetermined. The mould cavity 196 may be filled on the side 195 and mayalso be opened on that side, although release may also, if appropriate,take place on the other side. A membrane 197 lies over the heads of thepins 193, 194 and may, as described above, be a (packaging) film, forexample.

The mould 190 can also be used to exert a fixing pressure after themould cavity 196 has been filled, for example by moving the pins of oneof the mould halves slightly towards the other mould half.

To provide cohesion of the pieces of meat in the mould, local heatingmay be provided, so that the product becomes dimensionally stable as aresult of coagulation. As an alternative, it is possible to freeze themass in the mould cavity. In the case of these thermal treatments of themass in the mould cavities, it is deemed advantageous to arrange thermalinsulation between the mould cavities. When a meat mass is heated, fatmay be released, which fat may facilitate removal of the moulded productfrom the mould cavity.

FIG. 13 shows a perspective view of a moulding device 70 of the“rotating drum type”, for example designed as described above withreference to FIGS. 4-10, with an associated filling component 71. Tofeed the meat mass to the filling component 71, an extruder 72 isprovided, having an extruder screw 73 which can rotate inside anassociated extruder tube 74. The extruder 72 is fed with meat from astorage container 75, which meat is pounded by the extruder 72 and ispushed towards the filling component 71. The consistency and inparticular the viscosity of the meat mass coming out of the extruder 72are of great importance for the operation of filling the mould cavitiesof the moulding device 70 and for forming the moulded meat products.Therefore, the invention provides for additives to be added to the meatmass in the extruder 72 when necessary, in order to alter the viscosity.Furthermore, additives may be added to the meat mass at the extruder 72,preferably by means of feed means 76, 77 which are connected to theextruder tube 74. These additives may, for example, be spices,flavourings and colorants, water, egg white, etc., but it is alsoconceivable for another type of meat to be added. The additives are fedto the extruder tube 74 under pressure. Preferably, the pressure of themeat mass is regulated in the chamber of the filling component 71, insuch a manner that the pressure in that chamber is kept within apredetermined pressure range, for example by regulating the rotationalspeed of the extruder screw 73. As an alternative to an extruder screwas shown and described here, it is also conceivable to use a differenttype of conveying/mixing component for supplying and mixing the mass tothe moulding machine. By way of example, a ribbon mixer could be used.

FIG. 14 shows a variant embodiment of the device shown in FIG. 13, withwhich it is possible to produce layered products. This figure, inaddition to the components which are provided with the same referencenumerals as those in FIG. 13, also shows a special filling component 141with two connections, one for the extruder 72 and one for a secondextruder 142, which is only shown in part. In the filling component 141,each connection is adjoined by an associated system of passages whichhas branching passages which divide the streams of pounded foodstuffemerging from the extruders 72 and 142 into sub-streams. The passages ofeach system of passages each end at an associated outlet nozzle. Bysuitably designing the filling component 141 it is possible, forexample, to supply a plurality of alternating, adjacent sub-streams ofdifferent masses at the location where the mould cavity moves past thefilling component 141 and to place these different masses into the mouldcavity. In this way, it is possible, for example, for a product p tocomprise a middle strip 145 of a foodstuff delivered by extruder 72 andtwo outer strips 146, 147 of a foodstuff delivered by extruder 142. Thestrips 145-147 adjoin one another transversely with respect to thedirection of rotation of the drum 70. Obviously, a product may becomposed of even more strips and/or even more extruders could beconnected to the filling component 141.

It will be clear that if the mould cavities of the drum have theirfilling opening on the inside, the filling component 141 may also bearagainst the drum on the inside.

FIG. 15 a shows a variant embodiment of the device according to theinvention which makes it possible to produce a product with an internalfilling, for example a chicken product with an internal filling ofsauce, and/or a layered product.

The device 200 has a rotatable drum 202 with mould cavities 204, thebase 205 of which is able to move inwards and outwards, for example byforming the base as a piston which can be moved to and fro. The device200 comprises a first filling component 206 which, as seen in thedirection of rotation of the drum 202, is in this case located upstreamof the highest point of the path of the drum 202. On reaching the firstfilling component 206, the base 205 of the corresponding mould cavity204 is in a position which is located towards the outside with respectto the final thickness of the product which is to be produced. Thefilling component 206 is then used to fill the mould cavity 204 with a(meat) mass. Then, the base 205 moves inwards, and a hollow is pressedinto the (meat) mass by a hollow-pressing component 210 which is locatedalong the drum 202. The hollow may be of any desired form, including anannular recess. Then, a portion of filling is placed into the saidhollow by means of a filling-feed component 211. The filling may beliquid, but could also be solid, for example a block of frozen sauce oran edible body. In the case of a solid piece of filling, it would bepossible to dispense with the operation of forming the hollow.

After the filling has been placed in the hollow, a second layer of themeat mass is placed into the mould cavity 204 with the aid of a secondfilling component 213 which is located downstream of the first fillingcomponent. By introducing meat mass using the second filling component,the filling is completely enclosed between the two layers of meat mass.Furthermore, it is now possible to exert a fixing pressure on the massin the mould cavity 204, preferably in one of the ways described above,for example at the location of closure component 214. Then, the mouldedproduct with the internal filling can be ejected from the mould cavity204, during which operation the base 205 is moved outwards.

It will be clear that a product composed of a plurality of layers can beformed in each moulding cavity using a device which comprises aplurality of filling components which are arranged one behind the otherin the direction of rotation of the drum, with the mould cavities whichmove past the filling components having a moveable base, which base isthen moved in a stepwise manner in order to increase the size of themould cavity and in order to be able to accommodate a new layer of(meat) mass. This measure could also be combined with a fillingcomponent as described with reference to FIG. 14, so that various layerscan be formed both in the thickness and in the width of the product.

In a variant which is not shown, no filling is introduced into theproduct, but rather two products which are separated from one another bya film or the like are produced in one mould cavity. This is possible byarranging a film over the outside of the mould cavity after it has movedpast the first filling component 206, after which the base of the mouldcavity moves inwards, and then a following product is formed on the filmby means of the second filling component 213. As an alternative to film,a loose disc could also be used.

FIG. 15 b shows a moulding device 230 with two drums, 231 and 132respectively, which are positioned next to one another and are eachprovided with associated mould cavities 233 and 234 on the outercircumferential surface. The drums 231 and 232 are driven in rotation inopposite directions but at the same circumferential speed, by means ofdrive means (not shown). Furthermore, the cross-sectional dimensions ofthe openings of the mould cavities 233 and 234 are identical, so that,given a suitable arrangement of the drums 231 and 232, it is possible tomake two mould cavities 233 and 234 accurately adjoin one another. Inthis case, the delimiting edges of these two mould cavities bear tightlyagainst one another. To allow the drums to rotate, it is possible forone of the drums to be moved sideways to and fro with respect to theother drum during rotation. As an alternative, the delimiting edges ofthe mould cavities of one or both drums could be designed in such amanner that they can be compressed resiliently.

Each drum 231 and 232 has an associated filling component 235, 236, bymeans of which meat mass or the like can be introduced into a mouldcavity. On the downstream side of each filling component 235, 236, thereis an associated closure component 237, 238 with dimensions which aresuch that the component closes off a mould cavity at least while themould cavity is still in communication with the filling component. Inthis way, a completely filled mould cavity can be obtained in bothdrums, with the mass in the mould cavity projecting outwards withrespect to the plane running across the delimiting edges of the mouldcavity. As the drums 231 and 232 rotate further, the filled mouldcavities then come to lie next to one another, with the delimiting edgesof these mould cavities adjoining one another in a sealed manner andthus forming a completely closed space. By means of this measure, themass in this space is compressed with respect to the situation after ithas moved past the filling component, so that by means of thiscompression the mass in the closed space is subjected to a fixingpressure. Obviously, it is also possible to provide additional measuresfor controlling the fixing pressure, for example the use of film betweeneach of the drums and the mass which is to be fed, and the exertion of agas pressure between the drums and the film at the time at which the twomould cavities adjoin one another.

The fixing pressure produces adhesion between the pieces of meat, afterwhich the meat product p can be removed as a cohesive unit and can bedischarged via conveyor device 240.

It will be clear that the device 230, instead of having drums 231 and232, may also be produced with two turrets which run past one another,in which case, for example, the path over which the mould cavitiesadjoin one another, and therefore over which the fixing pressureprevails, can be extended further.

FIGS. 16 a and 16 b and 17 a-h show an alternative moulding device forproducing three-dimensional products from foodstuff. This devicecomprises a stationary central tube 310 which is preferably arranged atthe end of an extruder 302, as can be seen from FIG. 16 b. In thecentral tube 301 there is an opening 303, through which (meat) masswhich has been fed via the interior of the tube 301 can move out of thetube 301. A ring 305 which can be driven in rotation and is coupled to adrive motor, for example by means of a gear wheel/gear ring transmission306, lies around the outside of the tube 301.

The ring 305, together with the tube 301 which fits inside it, forms twosubstantially C-shaped chambers 308 and 309 which are located around thetube 301. These chambers 308, 309 each have an associated outlet 310,311, respectively, leading to the outside of the ring 305. A stationarycylindrical outer casing 312 with a single opening 313, which may bealigned with a matching outlet 310, 311, fits around the outside of therotatable ring 305. The outer casing 312 is arranged eccentrically withrespect to the tube 301.

The chambers 308 and 309 are separated from one another by inwardlyprojecting lobes 314, 315 on the ring 305, which lobes are designed insuch a way that, in the event of rotation of the ring 305, they continueto bear in a sealing manner against the tube 310.

The opening 303 and the opening 313 are arranged in such a way that, inthe event of rotation of the ring 305, they temporarily come intocommunication with the same chamber 308 or 309.

This device operates as follows. When the device starts up, the chamber308 will be filled via opening 303, this operation taking place for aslong as this chamber is in communication with the opening 303 (cf. FIGS.17 a-17 c). Then, the volume of the chamber 308 becomes ever smaller asa result of the eccentric arrangement of the ring 305 with respect tothe tube 301, until a minimum volume is reached (FIG. 17 e). As a resultof this reduction in volume, the mass in the chamber 308 is compressedby a pressure which is independent of the pressure with which the masshas been introduced into the chamber 308 via the opening 303. When thering 305 rotates further, the volume of the chamber 308 increases againand, as soon as the chamber 308 reaches the opening 303 again, furthermass will enter the chamber 308 adding to the already compressed mass(FIG. 17 g). As soon as the outlet of the chamber 308 then reaches theopening 313 in the outer casing 312 (FIG. 17 h), at that moment masswhich flows in via the opening 303 presses a portion of the alreadycompressed mass outwards via the outlet. It will be clear that the sameprocess takes place in chamber 309.

To regulate the pressure with which the mass is compressed, it ispossible for the device to be designed in such a manner that theeccentricity can be adjusted within a defined range.

FIGS. 18 a and 18 b show an embodiment of a moulding device 325according to the invention in which a mould comprises two mould halves326 and 327 which can move with respect to one another. The two mouldhalves 326 and 327 may, for example, be accommodated in a turret whichtransports the mould halves along a path. In this case, the design may,for example, be such that, in a bend in the path, the two mould halves326 and 327 are moved away from one another, as in FIG. 18 b, and in astraight part of the path bear against one another, so that the mould328 is then closed.

The mould half 326 is provided with a feed tube 329 for feeding the(meat) mass to the mould cavity 328. In this case, however, in the openposition of the mould, a balloon-like membrane 330 is placed in themould, with its opening connected to the feed tube 329, so that the massmoves into the balloon 330. The balloon 330 is preferably made from anelastic plastic material, preferably of a quality which is such that theballoon can be used directly as a packaging material for the mouldedproducts 331.

After the mould has been closed, mass is then introduced into theballoon 330, so that this balloon adopts the shape of the mould cavity328. After the filling has finished, the balloon already exerts a fixingpressure on the mass, but preferably additional measures are provided inorder to produce a controllable fixing pressure. For example, a pressuremedium can be placed between the mould and the balloon 330 viaconnecting passage 335, the pressure of which medium can be regulated inorder to control the fixing pressure.

When the fixing period has expired, the mould can be opened and themoulded product 331, which is packaged inside the balloon 330, can beremoved and discharged using discharge means 336.

The method according to the invention is described in claims 1-5, and anumber of moulding devices which are suitable for implementing thismethod are described in the following claims. However, the presentinvention also relates in part to the moulding devices themselves,independently of the method according to claims 1-5, a fact which couldbe represented by replacing the current wording “moulding device forcarrying out the method according to one of claims 1” by “Mouldingdevice for moulding three-dimensional products from a mass of foodstuffwhich is suitable for human consumption”. Furthermore, it will clearthat the present description, with reference to various figures,mentions numerous aspects which can be combined by the person skilled inthe art and may, for example, be implemented in a single mouldingdevice. It will be clear that the present application also relates tosuch combinations and devices.

1. A method for molding three dimensional products from a mass offoodstuff which is suitable for human consumption using a molding devicecomprising: a mold comprising a mold cavity defined by a base and acircumferential wall and having a cavity opening opposite the base; amass feed component; one or more first nozzles located in the base ofthe mold cavity; a first passage in communication with the one or morefirst nozzles; one or more second nozzles located in the circumferentialwall or in an annular area of the base adjacent the circumferentialwall; a second passage in communication with the one or more secondnozzles; a source for gas under pressure; and a selector device forselectively connecting the source to the first passage or the secondpassage, the method comprising: feeding the mass of foodstuff into themold cavity via the cavity opening with the mass feed component; moldingthe mass of foodstuff into a molded product; and removing the moldedproduct from the mold cavity by first bringing the second passage intocommunication with the source of gas under pressure, so that the moldedproduct is pressed away from the circumferential wall of the moldcavity, and then bringing the first passage into communication with thesource of gas under pressure, so that the molded product is removed fromthe mold cavity.